Seawater desalination is no easy task. Traditionally, vacuum
distillation techniques have been used, and this process requires a great deal
of energy. More recently, reverse osmosis facilities have come online. These
facilities use a special permeable membrane to separate salts and minerals from
liquid water. As of January, there are more than 13,000 desalination plants
pumping out over 12 billion gallons of water a day.

While cogeneration facilities have helped to cut down the cost of vacuum
distillation and reverse osmosis plants are marginally more efficient in terms
of energy used, work in the unrelated field of biology and molecular transport
systems may promise an even better type of filtering membrane for osmosis
systems.

Researchers at the Lawrence Livermore National Laboratory, while studying the
process of molecular
transportation across cell membranes, have come up with a new type of
filter. The filter mimics the properties of cell membranes and is especially
efficient in the transport and filtration of water molecules. Their work is
based on -- you guessed it -- carbon nanotubes.

What makes these CNT-based filters so efficient is their hydrophobic
properties, or the way they repel water molecules. Water moves through the CNT
channels in a membrane much more quickly than in conventional filters because
the molecules do not stick to the sides of CNTs. Instead, they stream through
them unhindered, like a bullet train.

After this discovery, the researchers tested their artificial membrane for
desalination efficiency. They found that the 1.6nm diameter tubes successfully
prevented the ions that make up salts from traversing while letting the water
molecules flow freely. The mechanism for this selectiveness lies in the small
diameter of the channel along with the charge held at the end of the nanotubes.

Aleksander Noy, a senior member of the LLNL research team explains, “while
carbon nanotube membranes can achieve similar rejection as membranes with
similarly sized pores, they will provide considerably higher permeability,
which makes them potentially much more efficient than the current generation of
membranes.”

While the LLNL findings promise a great deal for desalination and other
processes where similar filtering is used, some refinement will still be
required. The ability to construct membranes of different materials and control
the charge and diameter of the nanotube pores will weigh heavily into their
efficiency and usefulness in different applications.

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fair enough, there is no reasearch that has qualified CNTs to go on the list of known carcinogens.

the "inflammatory effects" are caused by damage done to the cells in the area --> cells must divide to replace damaged cells --> cancer risk. thats what I was pointing out. now, how much is required to cause these responses was left unclear in the papers I've read, as the papers were focused on CNTs curing cancer, not casuing it.

BACTERIA divide tens of thousands of times every day. your cells do not.

the only cells that do that in the human body are blood cells. STEM cells having to divide into 2 stem cells instead of stem and terminal cell is actually lowers the cells ability to retain genome integrity.

so yes you are at an increased risk of cancer.

There are two ways to "induce" cancer either killing off a lot of cells, which can leads to the second, and large scale gene damage

now the only reason your arm is not in any serious danger is because the trauma is over, CNTs stuck in your lungs don't go away and therefore repeatedly do damage to the same area.

If you worried about everything that 'increases risk of cancer' then I'm willing to bet you wouldn't be sitting in front of your computer because the EMF from your monitor could cause cancer. As could florescent lighting that more than likely surrounds the majority of us day to day, and cell-phone undoubtedly in their pockets. Every day there is another study that correlates some other thing to increasing the risk of/causing cancer.

As someone who has had his mother diagnosed with cancer, I still could care less as to what might cause it. I'd rather them focus on studies on how to cure it.

Ahh but they do emit EMF, meaning it will increase the risk of cancer, regardless of how much energy it takes to effectively damage DNA.

Anything that puts out any kind of radiation can increase your risk. Even if it is .000000001% its still an increase over someone who does not expose themselves to said radiation.

I'm just saying that everything can increase your risk of cancer. If you take the time to look around and do some research I'm sure you can find some study or another that relates any givin thing to increasing the risk of cancer. All in all I could really give less of a crap if these can increase the risk, so could anything else for that matter.

If these carbon nanotubes can filter out any givin chemical from water, meaning less disease in general, more usable materials etc. I'm not gonna cry about an increased risk of cancer since there is already so much out there that can do the same.

that link you provided has a very good graph that shows "harmful" radiation, they call it ionizing but I prefer to think of it as "can damage DNA", and things radiation that really does not have the energy to do much of anything to biomolecules

I also have another article in a IEEE spectrum magazine laying around that studies the effects of ionizing radiation emitted from mobile devices such as cell phones etc. to be of such insignificant value relative to the many other things we encounter in life. It is pretty insignificant and I feel safe around most forms of EM radiation. Although a EM Pulse to level a nuke would form still scares me :).